Celluloid record-blank.



' blanks, the commercial celluloid for cylin- THQEIAS A. EDISON, 0E LLEWELLYN' PARK, WEST ORANGE, NEW JERSEY, ASSIGNOIIR TO NEW JERSEY PATENT COMPANY, OF WEST ORANGE, NEW J ERSEY, A CORPORATION @E NEW JESEY.

' cnLLuLoIn RECdRD-BLANK.

Patented Dec. a, rear.

No Drawing. original application filed October 16,1912, Serial No. 720,472. Divided and this application .filed .Tune 7, 1917.

To all whom it may concern:

Be .it known that T, THOMAS A. EDISON, a citizen of the United States, and a resident of Llewellyn Park, West Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Tmprovements in Celluloid Record-Blanks, of which the following is a description.

My invention relates to celluloid articles, such as record blanks, and more particularly, but not exclusively, to those of cylindrical form, this application being a division of my co-pending application, Serial No. 720,472, filed Oct. 16, 1912. The object of my invention is to provide an improved record blank of the above type which is provided with a true and suitably colored surface capable ofreceiving an accurate impression froma sound record mold.

Celluloid may be obtained in the market in desired form and of desired thickness for the manufacture of sound'records and dricalrecord blanks being in the form of long tubes which'may be readily cut into sections of desired length. Records as heretofore molded from these tubes are defective in that upon reproduction they emit surface noises foreign to the selections recorded. 1

have discovered that this defect is due to the fact that the surface of the commercial celluloid is filled with small pits and other defects which are not efiaced and thereby prevent the accurate molding of the celluloid when, as has heretofore been done, the surface of thg celluloid in its coercial condition is pressed against the record surface of-the mold. In order to obviate this objection, I remove the defective outer por-.

tion of the commercial celluloid, as by abrasion or turning. In practice, ll find that the removal of anouter portion to a depth of .001 of an inch is suficient to produce a true surface which is capable of receiving a true impression of the record undulations without the defects producing the surface noises hereinbefore referred to.

The next step in the formation of my improved record blank consists in dyeing the outer surface of the celluloid-cylinder or other blank in such a manner as not to injure the elasticity, molding qualities, and other desired properties of the celluloid. The

I dyes I prefer to use, that is, anilin dyes, are

Serial N0. 173,359.

phor, which is one of the ingredients of celluloid, is soluble in alcohol and acetone, a solution of these dyes in either of the above solvents would, if applied to the surface of the celluloid blank, partly dissolve the camphor from the celluloid and injure the elas ticity of the blank and the capability of-the latter to be accurately molded. T obviate this objection by adding to a solution of the dye in alcohol or acetone suflicient water to prevent the camphor in the celluloid from going into solution when the dye is applied to the surface of the celluloid. I have obtained good results with a solution containing about two parts by Weight of water to one part by weight of alcohol solvent and three parts by weight of water to one part by weight of acetone solvent. Such solutions as those specified above, soften the celluloid sufliciently to permit proper absorption of the dye and at the same time prevent an injurious dissolution of the camphor.

Tn dyeing a record cylinder, I take a blank, the outer surface of which has preferably been prepared as described above and dip the same into the water containing solution described above for a suitable length of time, the depth of the color of the cylinder depending upon the strength of the solution surface capable of receivingan accurate rec-.

0rd impression. It has its outer surface suitably colored; and its elasticity and moldmg qualities are unimpaired. Accordingly,

when the record undulations are impressed therein it produces a sound record of greatly improved acoustic properties.

Having now described my invention, what I claim as new and desire to protect by Letters Patent is as follows:

1. A sound record blank or the like lib formed of celluloid, dyed With an acetone solution of dye and having the camphor of the celluloid undissolved, substantially as described.

2. A sound record blank or the like formed of celluloid, dyed with a Water containing acetone solution of dye and having the camphor of the celluloid undissolved, substantially as described.

3. A sound record blank or the like formed of celluloid, dyed with .an acetone solution of anilin dye and having the camphor of the celluloid undissolved, substantially as described.

4. A sound record blank or the like formed of celluloid, and having a surface formed by removing a thin surface portion of the celluloid, said blank or the like being dyed With an acetone solution of dye, and having the camphor of the celluloid undissolved, substantially as described.

5. A dyed sound record black or the like formed of celluloid, and having a surface formed by removing ,a thin surface portion of the celluloid, said blank or the like having the celluloid of the camphor undissolved, substantially as described.

This specification signed and witnessed this 1st day of June, 1917.

THOS. A. EDISON.

Witnesses FREDERICK BACHMANN, JAooB UNGER., 

